Why cant I use c++ syntax on Node.JS terminal?

I always wondered why I can't use C++ syntax on the Node.js terminal.

For example, V8 is a JavaScript engine that implements ECMAScript. Node.js itself is a C++ program that tells the V8 engine to use it's function. So these function are written C++ code hence this application should be able to take in C++ native syntax. Meaning if I were to type C++ code in the Node.js terminal, then the Node.js terminal should be able to pass those syntax to the C++ modules in the Node.js core and output successfully. But instead it gives a :